Locking container lid apparatus and method

ABSTRACT

A container lid includes a permanently or elastically deformed tamper evident feature that alerts the user that the container has been accessed. Moreover, the tamper evident feature requires no additional material and produces no extra waste.

FIELD OF THE INVENTION

The present invention relates generally to containers. More particularly, the present invention relates to tamper evident container lids.

BACKGROUND OF THE INVENTION

The food and pharmaceutical industries require the ability to safely ship their products to various locations responsible for the manufacturing of their products. Much of the raw materials are shipped in bulk and may be dangerous if the contents are either contaminated or spilled.

Although containers and lids may be used to alert the user that the contents have been accessed, often it is not readily apparent. The end user has to be aware of what the tamper evident feature entails and examine the container and the lid to determine whether the contents have been accessed. Also, tamper evident features may often be more expensive in that they may require more material. The removal of this material may cause excess waste that becomes an additional source of cost when disposing the excess waste.

Accordingly, it is desirable to provide a re-usable tamper evident lid where any tampering is obvious to the user without undue examination and the tamper evident device does not produce excess waste. Moreover it is desirable that the tamper evident device minimizes manufacturing cycle time, uses less material and is cost effective. It is also desirable that the tamper evident lid contributes to the overall structural integrity of the enclosed container, such that if the container is dropped or mishandled, it does not open and spill its contents.

SUMMARY OF THE INVENTION

The foregoing needs are met, to a great extent, by the present invention, wherein in one aspect an apparatus is provided that in some embodiments provides a re-usable tamper evident lid where any tampering is obvious to the user without undue examination and the tamper evident device does not produce excess waste. Further, in some embodiments the tamper evident device minimizes manufacturing cycle time, uses less material and is cost effective. Also, in some embodiments the tamper evident lid contributes to the overall structural integrity of the enclosed container, such that if the container is dropped or mishandled, it will not open and spill its contents.

In accordance with one embodiment of the present invention, a closure assembly for a container having a sidewall, includes a top having a periphery, a skirt extending from the periphery, a pull tab having an opening and disposed on the skirt, a rib configured to detachably engage the container, disposed on the pull tab extending inwardly and substantially in parallel with the top, and a first groove and a second groove disposed on the skirt on either side of the pull tab.

In accordance with another embodiment of the present invention, a closure assembly system for a container having a sidewall, includes a top having a periphery, a skirt extending from the periphery, a pull tab having an opening and disposed on the skirt, a locking means configured to detachably engage the container, disposed on the pull tab extending inwardly and substantially in parallel with the top, and a first indicating means and a second indicating means disposed on the skirt on either side of the pull tab.

In accordance with yet another embodiment of the present invention, a method of indicating an open container having a sidewall includes providing a top having a periphery, providing a skirt extending from the periphery, providing a pull tab having an opening and disposed on the skirt, locking the container via a rib detachably engaging the container disposed on the pull tab extending inwardly and substantially in parallel with the top, and indicating via a first indicating means and a second indicating means disposed on the skirt on either side of the pull tab.

There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto.

In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting.

As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a cylindrical container with a lid according to an embodiment of the invention.

FIG. 2 is a cutaway outside perspective view of an outside of the lid.

FIG. 3 is a cutaway inside perspective view of an inside of the lid.

FIG. 4 is a perspective view of tear grooves, according to an embodiment of the present invention.

FIG. 5 is a perspective view of stretch grooves, according to another embodiment of the present invention.

FIG. 6 is a side view of the engagement of the lid with the container.

DETAILED DESCRIPTION

Some embodiments in accordance with the present invention provide a re-usable tamper evident lid where any tampering is obvious to the user without undue examination and the tamper evident device does not produce excess waste. Further, in some embodiments the tamper evident device minimizes manufacturing cycle time, uses less material and is cost effective. Also, in some embodiments the tamper evident lid contributes to the overall structural integrity of the enclosed container, such that if the container is dropped or mishandled, it will not open and spill its contents. The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. The numerals generally represent features while the letter “a” beside the numeral represents the external aspect of the item and the letter “b” represents the internal aspect.

FIG. 1 is a perspective view illustrating a cylindrical container 10 with a lid 11 according to a preferred embodiment of the invention. An embodiment of the invention includes a readily apparent temper-evident feature that is inexpensive and produces no excess waste. In particular, the lid's tamper evident feature provides an easily recognizable indication that the container has been opened. The container 10 may be any type of container as discussed herein.

The present invention addresses a lid for closure over conventional containers which advantageously may be formed with a molded plastic material such as a polyolefin. A primary latching feature is incorporated within the lid structure.

For utilization of the container on a day-to-day basis following the removal of the primary latching assembly, a secondary latching assembly is incorporated which remains intact and is readily disengaged and engaged from the rim structure of the container by hand and without tools. Thus, a lid structure is provided which promotes the day-to-day proper closure of the lid assembly by those accessing the contents of the associated container. Preferably, this latter attachment of locking of the lid by the filling entity is provided by a “tamper evident” technique where any subsequent opening involves a readily apparent destruction of the primary latching structure.

FIG. 2 is a cutaway outside perspective view of an outside of the lid 11 while FIG. 3 is a cutaway inside perspective view of an inside of the lid 11. The lid 11 has a center panel 12 that in some embodiments is flat and circular. The lid 11 may be formed of an integrally molded polyolefin form of plastic. At the center panel's 12 peripheral edge is a chime 14 that facilitates stacking, along with a stacking rib 16. Both the chime 14 and the stacking rib 16 are generally perpendicular to the center panel 12. Although, containers themselves are somewhat similar, lid structures for containers vary.

Typically, containers are made of a fiber or cardboard material depending on the substances they carry. However, metals and plastics are also used to fabricate these containers. Cost saving may be achieved by using fiber containers instead of plastic or metal containers. However, fiber containers may still have metal or plastic lids attached with two or more clips cleated to the container body portion. In addition, once a conventional lid has been opened once, it may be difficult to securely close it thereafter. Thus, secondary closing features are valuable not only to an end user but also during shipping of the container and lid to the filling site.

Containers having capacities of eight gallons to fifty gallons are referred to as drums, while intermediate size containers having capacities between three and seven gallons are referred to as pails. Smaller containers with capacities from four ounces to two pounds are referred to as tubs.

Generally, the materials to fabricate these drums range from about fifty to five hundred pounds per drum and when filled are handled by personnel using hand carts or forklifts due to their weight. Some of the containers may be tipped over or dropped during such handling. Therefore, having secure lids is important to avoid spillage of the contents.

To reinforce the lids, the rims of the containers may be braced with annular metal chimes with a rim bead in an inwardly extending region or groove just below the bead, the mounting of which effects a deforming securement to the drum wall and which is used to aid in securing lids to the drum. The lids may be formed as stamped metal components which are secured over the rim-chime assemblies with metal locking rings to assure the lid tight security of the drums if tipped or dropped.

Conventionally, to open a container, a user released and removed a locking ring. This removed the lid and exposed the contents of the container. To close the container, the lid is repositioned, the locking ring is remounted and tightened. This open-close process may be tedious where the contents are repeatedly accessed. Often the lids may be placed loosely on the container rim and the locking ring feature ignored by the user who tires of securing the lid each time the container is opened. This leaves the container unsealed and may degrade its contents. In addition, this may allow for dangerous aspects to be added to the contents.

Pails may be made of plastic, with container bodies of a frusto-conical shape. The lids may be discoidal in shape and may also be made of plastic. Usually, these lids may be locked in place or opened with tools such as a screw driver. The use of such tools may dissuade a user from properly securing the lid as the user repeatedly opens and closes the lid. To retain lids on pails, the pails include an integrally molded rim structure which contains an upwardly disposed rim bead, as well as an engaging region formed inwardly and below the bead.

Tubs are usually formed using thermoformed or injection molded materials. The smaller tub structures are generally configured of a vacuum formed, thermoformed, or injection molded material and the lid considerations for them look to the provision of a “tamper evident” feature. In the latter regard, it is desirable for many products to provide an indication as to whether any unauthorized opening of the lids of the tub has occurred subsequent to their being filled, for example with edible products. For the most part, the tamper evident procedures have been designed for that feature alone and not with considerations of improving the seal security of the lid-container combination in the first instance.

Here, in one embodiment of the present invention, the lid may also provide a tamper evident feature in that there is an indication as to whether any unauthorized opening of the lid has occurred. The tamper evident feature provides for a destruction of the primary latching structure. This is very beneficial in both the food industry and in the pharmaceutical industry.

Stacking considerations are finding importance in both container and lid designs. Two aspects for such stacking occur, one stemming from requirements for transporting the containers empty, inasmuch as they maybe transported separately and the second consideration concerns the warehousing of the filled containers with lids attached.

Where lids are transported, it is desirable that they be stackable in some form of nesting relationship to facilitate their movement in the factory environment both where they are produced and at such time as they are employed to close a filled container. Particularly in the case of drums, the heavy weights involved become considerations in terms of warehousing and the like. Where pails and tubs are concerned, stacking requirements for both warehousing and retail display are assuming higher levels of importance. In some applications, it is preferred to pre-attach lids to containers for the purpose of a stacked shipment of the entire assembly. For such application the secondary latch is received following filling of the container.

The ability to stack containers is also desirable. It results in space savings as well as cost savings. Lid design is therefore, an important consideration in stacking containers. One aspect results from shipping containers and lids to the packing manufacturer where the containers and lids may then be transported separately. When the lids are transported separately, it is desirable that they may be stacked to facilitate their movement both when they are produced and when they are utilized at the filling site to fill the containers. In some applications it may be beneficial to ship the entire assembly with the lid attached to the container.

Another aspect is the warehousing of the filled containers with lids in place. When filled, the containers may be very heavy and therefore structural integrity is an important consideration, as is storage. Being able to stack filled containers allows for space savings.

A lid for use with containers such as drums, pails, tubs and cups which is formed as a singular unit from molded plastic and which incorporates a peripherally disposed skirt configured along with a rim structure to provide primary and secondary latching features.

Referring to FIGS. 2 and 3, the chime 14 and the stacking rib 16 provide for the ability to stack the lids for ease of storage during manufacturing and shipping. Both are integrally molded with the lid assembly. Extending downwardly from and substantially in parallel to the stacking rib 16 is a skirt 20 of the lid 11. The skirt 20 is also integrally molded with the lid 11. The skirt 20 and the chime 14 together form a gasket channel 18 that engages the rim portion (not shown) of a drum when the lid 11 seals the drum. The gasket channel 18 also engages the stacking rib 16 when one lid is stacked on another.

The skirt 20 has a stiffening rib 22 that adds strength to the lid 11. Perpendicular to the stiffening rib 22 is a lower skirt 24 that is parallel to and is an extension of the skirt 20. Attached to the skirt 20 is a pull tab 26. In another embodiment of the present invention, several pull tabs may be formed on the lid and may be circumferentially spaced about the lid. The number and spacing, of the pull tabs may vary depending on the strengthening requirements of the lid and container assembly.

The pull tab 26 has a finger hole 28 through which an user can insert a finger (not shown) and grasp the pull tab 26. Above the pull tab 26 and adjacent the skirt 20 is an indented upper skirt 30. On either side of the indented upper skirt 30 are tear or stretch grooves 36 and 38.

Between the finger hole 28 and the indented upper skirt 30 are mold core opening 32 and a locking rib 34. The locking rib 34 provides a locking function in that it detachably couples to the container rim (not shown). The locking rib 34 engages the rim of a container and secures the lid 11 to the container, ensuring that the lid 11 is not easily removed from the container.

Pulling on the pull tab 26 releases the locking rib 34 from its engagement with the container, allowing the lid 11 to be removed from the container. This can be repeated as often as needed to access the contents of the container. However, when the pull tab 26 is pulled for the first time and the locking rib 34 is disengaged from the container, the tear grooves 36 on either side of the indented upper skirt 30 and the pull tab 26 are torn. Correspondingly, in another embodiment, the stretch grooves 38 on either side of the indented upper skirt 30 are stretched, or deformed elastically.

FIG. 4 is a perspective view of tear grooves 36, according to an embodiment of the present invention. The tear grooves 36 rip when the pull tab 26 is used and are permanently deformed. The tear is an obvious indication to the user that the contents of the container have been accessed already. The tearing of tear grooves 36 perform a function of indicating that the container has been opened. The lid 11 cannot be removed without tearing the tear groove 36. When there are multiple pull tabs 26 placed circumferentially around the lid 11, each of the pull tabs 26 has to be pulled and the tear grooves 36 ripped, for the lid 11 to be removed from the container. This tear is readily apparent and produces no excess waste.

Such a tear is an obvious indication to any one who requires information as to whether the contents have been accessed. The tear also does not require additional material. Conventional tamper evident features involve tearing and discarding excess packaging. Thus, a user who is not accustomed to this particular type of feature may be unaware of it entirely and fail to recognize that the container has been accessed. This can have adverse effects to the manufacturer and consumer.

A conventional tamper evident feature may also produce excess waste. Thus, as the container is accessed, it produces waste that must be discarded. A manufacturer who uses a large number of containers and accesses them will have to discard such a large amount of waste that it becomes an expensive endeavor. The tamper evident feature of the presently claimed invention has the additional feature of being inexpensive to produce in that no excess material is required to be discarded for the feature.

FIG. 5 is a perspective view of stretch grooves 38, according to another embodiment of the present invention. The locking mechanism has a stretch groove 38 on either side of the indented upper skirt 30 and the pull tab 26, instead of the tear groove. The stretch groove 38 will allow the locking rib to disengage from the container by elastically deforming when the pull tab 26 is pulled. The elastically deformed stretch grooves 38 also indicate that the container 10 has been opened.

An advantage of the stretch groove 38 is that no remnants from the tear groove 36, or loose particles from the tear groove 36 may contaminate the area or the contents of the container. This is particularly useful when the contents of the container are of a sensitive nature and must be completely free of any impurities. As with the tear groove 36, no additional material is required to produce the stretch groove.

In both instances, the pull tab 26 can be re-engaged with the container by engaging the locking rib 34 to the container rim. This secures the lid 11 to the container but the tear on the tear groove 36 and deformation on the stretch groove 38 serve to make evident that the primary locking mechanism has been tampered and disengaged and that the contents may have been accessed.

FIG. 6 is a side view of the engagement of the lid 11 with the container 10. The container 10 is configured to mate with the lid 11 such that the container sidewall 42 has a ridge 44 that mates with the mold core opening 32. Further, the container sidewall 42 has a top edge 46 that rests within the chime 14 of the lid 11. Thus, this lid 11 may preferably be used with containers 10 configured to mate with the lid 11 in a similar manner. In an embodiment of the present invention, the lid 11 may assemble with a twenty gallon drum used to house Teflon.

The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. 

1. A closure assembly for a container having a sidewall, comprising: a top having a periphery; a skirt extending from the periphery; a pull tab having an opening and disposed on the skirt; a rib configured to detachably engage the container, disposed on the pull tab extending inwardly and substantially in parallel with the top; and a first groove and a second groove disposed on the skirt on either side of the pull tab.
 2. The assembly of claim 1, wherein the first groove and the second groove are configured to tear.
 3. The assembly of claim 1, wherein the first groove and the second groove are configured to deform elastically.
 4. The assembly of claim 1, wherein the closure assembly has a plurality of pull tabs disposed on the skirt.
 5. The assembly of claim 4, wherein the plurality of pull tabs are circumferentially spaced around the skirt.
 6. The assembly of claim 4, wherein the plurality of pull tabs comprises two pull tabs.
 7. The assembly of claim 4, wherein the plurality of pull tabs comprises three pull tabs.
 8. The assembly of claim 1, wherein the top is configured with a stacking rib adjacent the periphery.
 9. A closure assembly system for a container having a sidewall, comprising: a top having a periphery; a skirt extending from the periphery; a pull tab having an opening and disposed on the skirt; a locking means configured to detachably engage the container, disposed on the pull tab extending inwardly and substantially in parallel with the top; and a first indicating means and a second indicating means disposed on the skirt on either side of the pull tab.
 10. The system of claim 9, wherein the first indicating means and the second indicating means are configured to tear.
 11. The system of claim 9, wherein the first indicating means and the second indicating means are configured to deform elastically.
 12. The system of claim 9, wherein the closure system has a plurality of pull tabs disposed on the skirt.
 13. The system of claim 12, wherein the plurality of pull tabs are circumferentially spaced around the skirt.
 14. The system of claim 9, wherein the top is configured with a stacking locking means adjacent the periphery.
 15. A method of indicating an open container having a sidewall comprising: providing a top having a periphery; providing a skirt extending from the periphery; providing a pull tab having an opening and disposed on the skirt; locking the container via a rib detachably engaging the container disposed on the pull tab extending inwardly and substantially in parallel with the top; and indicating via a first indicating means and a second indicating means disposed on the skirt on either side of the pull tab.
 16. The method of claim 15, wherein the first indicating means and the second indicating means are configured to tear.
 17. The method of claim 15, wherein the first indicating means and the second indicating means are configured to deform elastically.
 18. The method of claim 15, wherein the closure method has a plurality of pull tabs disposed on the skirt.
 19. The method of claim 18, wherein the plurality of pull tabs are circumferentially spaced around the skirt.
 20. The method of claim 15, wherein the top is configured with a stacking rib adjacent the periphery. 